Between the infusion containers and the drip chamber in general there is provided a valve for controlling the amounts. This function in the known valves is supplemented by the construction of the valve as check valves. Such check valves may contain a diaphragm disk (see, for example, DE 40 39 814 A1; DE 43 04 949 A1). Depending on the pressure on the front or rear sides of the diaphragm disk, a flow path is opened or closed permitting fluid to flow from the infusion containers.
In the present case, there exists the problem that after draining one infusion container, a fresh full container must replace the empty container, which usually requires a number of manual steps.